1. Field of the Invention
The present invention relates to a sport boot of the so-called "stiff shell" type and to an adjustable stiffening device adapted to modify the characteristics of the boot sole, particularly in its longitudinal direction, so as to adapt the general stiffness of the boot and therefore its behavior, for a specific use, especially when it is fixed on an equipment or accessory, such as, for example, a ski, a skate, spikes, etc., necessary for certain athletic practices.
2. Description of Background and Material Information
The known sport boots of the aforementioned type, such as those described in French Utility Certificate No. 2 391 666, French Patent Publication No. 2 310 719, and French Patent Publication No. 2 714 800 have adjustable stiffening devices which consist of integrating into the sole or retaining therein at least one rigid element so as to modify the stiffness of the sole and, consequently, the general stiffness of these boots.
More specifically, these stiffening devices have at least one removable rigid element that extends in the longitudinal direction of the sole, and at least one means for assembling the element to the sole adapted to join them in order to achieve their coupling. In these boots, it is also taught that the adjustment of their stiffness can occur by replacing, in the sole, a rigid element having a given stiffness with another rigid element having a different stiffness.
These ways of modifying the stiffness of soles, and thus of boots, give full satisfaction as to the result but still require a mounting-dismounting operation for at least one assembly means, as well as the removability of at least one rigid element with respect to the sole, whether it is to weaken or reinforce the latter. Consequently, depending on the adjustment made, the user is obligated to provide a storing area that is not integrated with the boot, for the rigid element that is not used or for the removable rigid element having characteristics that are different from the one implemented and adapted to replace the latter in the case of a particular use of the boot.
Obviously, in certain examples of construction of these stiffening devices, as seen in their description in documents FR 2 310 719 and FR 2 714 800, it suffices to remove the assembly means to couple the rigid element to or release it from the sole through the interior of the boot, and thus to modify the stiffness of the sole without manipulating the rigid element. However, in this possibility, it is then necessary to provide a storing for the assembly means which is dismounted from the sole.